WO2020200598A1

WO2020200598A1 - Brake regulating device, braking method, and brake system for a rail vehicle

Info

Publication number: WO2020200598A1
Application number: PCT/EP2020/055318
Authority: WO
Inventors: Ulf Friesen; Marc-Gregory Elstorpff; Rupert Lang; Ralf FURTWÄNGLER
Original assignee: Knorr-Bremse Systeme für Schienenfahrzeuge GmbH
Priority date: 2019-04-01
Filing date: 2020-02-28
Publication date: 2020-10-08
Also published as: US20220169223A1; DE102019108447A1; CN113661101A; JP7263548B2; JP2022527519A; KR20210142195A; KR102642681B1; EP3947067A1; EP3947067B1

Abstract

The invention relates to a brake regulating device (2) for a rail vehicle, having an input (21) for a target deceleration value (ä_set), an input (22) for an actual deceleration value (a_train), and an output (23) for a deceleration control variable value, said deceleration control variable value (a_0Ut) being set by a regulating unit in order to minimize a deviation between the actual deceleration value (a_train) and the target deceleration value (a_set). The brake regulating device (2) is characterized in that a limiting device is provided which limits the deceleration control variable value (a_out) independently of the regulating unit such that the deceleration control variable value (a_out) deviates from the target deceleration value (a_set) maximally by a maximum negative control stroke (14) to lower values or maximally by a maximum positive control stroke (15) to higher values. The invention additionally relates to a braking method and a brake system for a rail vehicle.

Description

Brake control device, braking method and braking system for one

Rail vehicle

The invention relates to a brake control device for a rail vehicle, which has an input for a deceleration setpoint and an input for a

Has actual delay value and an output for a delay manipulated variable value. In the brake control device, the manipulated variable value is determined by a

Control unit set to minimize any discrepancy between the actual deceleration value and the nominal deceleration value. The invention also relates to a

Brake system for a rail vehicle with such a brake control device and an operating method for a brake system.

Brake systems for rail vehicles have, in addition to regenerative brakes and supporting brakes, such as eddy current brakes, friction brakes, for example disc or block brakes. Environmental influences such as wetness, snow or ice in particular reduce a coefficient of friction of the friction partners of these brakes, for example the coefficient of friction between the brake lining and the brake disc. In order to achieve a predictable braking result in spite of variable friction values, control loops are used to ensure a requested and expected deceleration of the

Compare the rail vehicle with an actually achieved deceleration and readjust a manipulated variable of the braking system, for example a braking force.

A brake system with such a control device is known, for example, from the document DE 10 2015 110 053 A1. With this system will be

Acceleration components of the rail vehicle determined, with as

In addition to a longitudinal deceleration, a vertically acting deceleration is also determined in order to be able to separately take into account the effect of a downhill force. The document DE 10 2011 052 545 B4 also describes a brake system with a brake control device, in which actual deceleration values are measured redundantly and averaged in order to increase security for the correct functioning of the

To achieve braking system. FIG. 5 shows the behavior of a controlled system of a control loop for such a controlled brake system according to the prior art.

In the diagram, a progressing time t is shown on the horizontal axis and a predetermined target value, here a predetermined one, on the vertical axis

Acceleration setpoint ä _set. In a curve 11 is a requirement on the

Brake system with regard to the delay to be taken a _set time-dependent

reproduced. The curve 11 rises in two steps from an initial value a _set = 0 via an intermediate value to a requested maximum value of the delay to be achieved. A braking situation is thus reproduced in which slight braking is to be carried out for a certain time and then stronger braking.

A lower control limit 12 and an upper control limit 13 are shown around the curve 11. These two limits 12, 13 indicate a control range within which a brake control device according to the prior art can modify the requested deceleration in order to get as close as possible to the requested deceleration according to curve 11 with an actually measured deceleration. The situation shown results from the control behavior of a control unit of the control loop, which is constructed here as a proportional controller, for example. A maximum positive control stroke 14 and a maximum negative control stroke 15, which are shown in FIG. 4 by arrows, correspond to the control limits 12, 13.

According to the state of the art, for the proportional controller mentioned, the maximum positive control stroke 14 and the maximum negative control stroke 15 for a requested delay value are the same and a specific one

the specified percentage of the currently requested delay value.

In reality, however, occur especially with those mentioned at the beginning

Environmental conditions such as wetness, snow or ice between the friction partners have effects that can only be inadequately compensated for by the control loop described. For example, the environmental influences mentioned have a greater effect with lower braking requirements than with higher braking requirements. One reason is, for example, that during heavy braking due to the heating of the Friction partner (energy input) Moisture evaporates and the negative effect is reduced during braking (effect of "braking dry").

It is an object of the present invention to create a brake control device, a brake system and an operating method for a brake system which lead to optimal braking results even with changed friction properties between the friction partners of the brake system, in particular due to wetness, snow or ice.

This task is achieved by a brake control device, a brake system or an operating method for a brake system with the respective features of

independent claims solved. Advantageous refinements and developments are given in the dependent claims.

A brake control device according to the invention of the type mentioned at the outset is characterized in that, independently of the control unit, there is a limiting device which limits the deceleration manipulated variable value in such a way that the deceleration manipulated variable value changes from the deceleration setpoint by at most a maximum negative control stroke to smaller values or at most a maximum positive control stroke deviates to larger values.

The limiting device according to the invention makes it possible to control the maximum positive or negative control stroke independently of the selected control behavior of the control unit. This way you can get optimal at the same time

Control parameters can be selected and it can be ensured that no too large control stroke occurs. In this way, optimal braking results can be achieved, especially in difficult conditions such as wetness and / or snow.

When a brake control circuit with a proportional controller is used, the prior art also results in a control characteristic in which the maximum control strokes are limited. However, this behavior is limited to the use of a purely proportional controller, which shows only inadequate control behavior. In addition, an inherent limitation of the control stroke set in this way is inflexible because the maximum stroke in positive and negative direction proportional to the

Delay setpoint is. However, this behavior does not lead to optimal braking results, especially when it is wet and / or snowy. In an advantageous embodiment of the brake control device, at least one of the two maximum control strokes is therefore selected to be non-proportional to the deceleration setpoint.

In a further advantageous embodiment of the brake control device, the sum of the maximum negative control stroke and the maximum positive control stroke is a predetermined fixed value. The maximum negative control stroke can be selected to be different from the maximum positive control stroke. In this way, especially in the case of smaller deceleration setpoints, that is to say in the case of lower braking requirements, higher braking forces are made possible, which bring about a higher input of energy, which can compensate for a reduced braking effect due to moisture and that

Brake system can be conditioned.

In a further advantageous embodiment of the brake regulating device, the positive and / or the negative maximum regulating stroke are time-dependent, in particular such that it is lowered after a predetermined braking time. In this way, a maximum energy input into the brake can be limited and e.g. the effect of the

“Dry braking” of the brake must be taken into account. It can be provided that the maximum positive control stroke is only time-dependent when the deceleration setpoint is below a predetermined limit value. Similarly, it can be provided that the maximum negative control stroke is only designed as a function of time if the deceleration setpoint is above a further value

predetermined limit is.

In a further advantageous embodiment of the brake control device, at least one of the two maximum control strokes is predetermined by a characteristic curve or a characteristic curve field that is dependent on the deceleration setpoint and / or the braking time. Furthermore, at least one of the two maximum control strokes can be dependent on external influencing variables. External influencing variables can be (measured or otherwise determined) environmental conditions such as temperature or humidity Driving conditions of the rail vehicle, in particular a driving speed, a brake pressure, a braking force and / or an activation of an anti-skid system.

In a further advantageous embodiment of the brake control device is the

Limiting device coupled to the control unit to operate on parameters of the

Acting control unit depending on a limitation. In this way, greater stability of the control loop can be achieved when the limiting device responds. If the control unit is e.g. has an integral control component, an integrated value of the difference between the actual delay value and the nominal delay value would continue to rise (or fall) while the limiting device is already limiting the output delay manipulated variable value. In a subsequent changed braking situation in which the

Delay manipulated variable value is not limited, would be by the integral

Control component too large (or too small) a manipulated variable value output.

A brake system according to the invention for a rail vehicle is characterized by such a brake control device. The advantages described in connection with the brake control device result.

In an operating method according to the invention for a brake system

Rail vehicle is a deceleration manipulated variable value dependent on a

Delay setpoint and a delay actual value are set by a control unit to avoid a deviation between the delay actual value and the

To minimize deceleration setpoint. The method is characterized in that the delay manipulated variable value is limited in such a way that the delay manipulated variable value can deviate from the delay setpoint by at most a maximum negative control stroke to smaller values or at most by a maximum positive control stroke to larger values. At least one of the two maximum control strokes is preferably not proportional to the deceleration setpoint. Further preferably, at least one of the two maximum control strokes is determined as a function of the deceleration setpoint and / or the braking time and / or ambient conditions and / or driving conditions. The invention is explained in more detail below on the basis of exemplary embodiments with the aid of figures. The figures show:

FIG. 1 shows a block diagram of a controlled system of a brake system;

FIGS. 2-4 each show a diagram to illustrate the behavior of a controlled system of a brake system according to the application; and

FIG. 5 shows a diagram to illustrate the behavior of a braking system according to the prior art.

In FIG. 1, a controlled system 1 of a braking system according to the application is shown in the form of a block diagram. The controlled system 1 includes a

Brake control device 2, which is specified via an input 21, a deceleration setpoint a _set . The deceleration setpoint a _set is specified, for example, by a higher-level brake control system from a state of the rail vehicle. The brake control device 2 has a second input 22, an actually measured Verzögerungsistwert a _t is supplied to rain. The measured actual deceleration value atrain can be made available, for example, via acceleration sensors and / or via a GPS (Global Positioning System).

The brake control device 2 also has an output 23 at which a

modified delay _{value is} output as delay manipulated variable a _out . The exact function of the brake control device 2 is explained in more detail below in connection with FIGS. 2 and 3.

The deceleration manipulated variable a _out output by the brake control device 2 is fed to an input 31 of a manipulated variable converter 3. The manipulated variable converter 3 determines from the deceleration manipulated variable a _out a braking force F that is applied to a

Output 32 is output. The braking force F is the manipulated variable for the other components of the braking system. It specifies a cumulative force to be achieved by the brakes of the brake system and is determined from the deceleration manipulated variable a _0Ut , taking into account the mass of the rail vehicle, among other things. The value for the Braking force F is transmitted via an input 41 to a distributor 4, which the

Braking force on different axles and / or different brakes and / or different types of brakes of the rail vehicle and outputs at corresponding outputs, here for example two outputs 42, 43 for different axles of the rail vehicle axle braking forces Faxie i and Faxie _n .

Without the brake control device 2 according to the application, the predetermined delay a _set to be achieved could be transmitted directly to input 31 of the

Manipulated variable converter 3 are directed. This would output the braking force F in a controlled manner, taking into account the mass of the rail vehicle. In the case shown, the braking force F is modified in that, instead of the predetermined delay a _set to be achieved, the modified value of the delay manipulated variable a _{out is} fed to the manipulated variable converter 3, which outputs a modified value for the braking force F accordingly. In an alternative embodiment of the

according to the application braking system could also be based on the regulation

Braking force F take place in which the braking force F is modified instead of the deceleration by a corresponding brake control device. However, the system presented is advantageous in that when the control acts on the

Deceleration setpoint, a conversion taking into account the vehicle mass only needs to be done once and not separately for a precontrolled and a control component.

Figure 2 shows in the same way as Figure 5 described above

Properties of a controlled system of a brake system according to the application in a first exemplary embodiment. The curve 11 shows the same braking situation as in FIG. 4, in which a requested deceleration a _{set is set} from the value 0 in increasing steps. Again, there is a lower and an upper

Control limit 12, 13 and the corresponding maximum negative control stroke 14 and the maximum positive control stroke 15 are shown.

When setting the higher setpoint value specification for the delay a _set , the behavior known from the prior art, in which the maximum positive and the maximum negative control stroke 14, 15 are equal, is shown. For the one in the right part of the figure 2, which can be requested, the control stroke 14, 15 can also be selected to be just as large as it is in the braking system according to the prior art.

In the case of a smaller predetermined nominal deceleration value a _se t (left part of the diagram), however, the distance between the lower and upper control limits 12, 13 is just as large as in the case of the requested maximum value of the deceleration a _se t in the right part of the figure. The width of the control range is therefore independent of the setpoint specification, i.e. it is constant over the entire specification range. As Figure 2 also shows, takes place

Division of the control range into the maximum positive control stroke 15 and the maximum negative control stroke 14, but with a smaller default value in such a way that a larger, maximum positive control stroke 15 is present. The control range is therefore not centered around curve 1 1 with smaller setpoint specifications. This regulating behavior takes into account the fact that precisely when the braking process begins with a smaller deceleration value, moisture has a negative impact, which can be compensated for by the larger maximum positive regulating stroke 15.

Due to the separation of the control unit and

Limiting device can determine the type of control (e.g. proportional and / or differential and / or integral control) and the control parameters used completely independently of the control limits, i.e. the maximum positive or negative control strokes 14, 15 can be selected.

FIG. 3 shows a further exemplary embodiment for the behavior of a controlled system of a brake system according to the application. The illustration and braking situation again correspond to those shown in FIGS. 2 and 5, respectively.

In this example, the control limits are kept absolute and asymmetrical in the case of lower braking requirements (aset small), as in the example in FIG. However, this only takes place for a limited time, with from a certain firmly defined or also dynamically calculated time during the braking process from the control limits 12, 13 shown in FIG. 2 in a transition area to those shown in FIG

Control limits 12, 13 are changed. In particular, the initially larger one maximum positive control stroke 15 is reduced to the smaller value of the maximum negative control stroke. This initially enables an advantageous

Braking behavior in order to eliminate moisture or comparable environmental influences, however, then guarantees a limitation of the energy input in the case of prolonged braking, which would otherwise take place in the event of excessive braking.

Such a time-dependent behavior of the maximum positive control stroke 15 can also be implemented for the maximum negative control stroke 14. This is shown in the example in FIG. 4, in which both control strokes 14, 15 are time-dependent. As is also shown in FIG. 4, the time dependency itself can be different for the two control strokes 14, 15. The shape of the

Time dependency can be different from the linear time dependency shown here as an example.

FIGS. 2 to 4 merely show exemplary embodiments of control limits or control strokes which do not result strictly relative to the specified deceleration setpoint, but rather in a different functional context to the specified

Delay setpoint and / or are time-dependent.

It goes without saying that any functional relationship can be used for the specified deceleration setpoint. The functional relationship is preferably optimized in such a way that the best possible conditioning effect is achieved for every desired deceleration with insufficient braking effect

Friction partner, for example a drying of the existing moisture, is achieved.

The functional relationship or a characteristic curve resulting therefrom can also be made dependent on other influencing variables, for example on ambient conditions such as temperature and / or humidity, and / or on driving conditions such as vehicle speed, wheel speed, brake pressures or braking forces and / or activities of an anti-skid system. As shown in FIGS. 3 and 4, a function over time can also be introduced, for example to limit the maximum energy input. REFERENCE MARK

1 controlled system

11 Requirement curve

12, 13 control limit

14 maximum negative control stroke

15 maximum positive control stroke

2 brake control device

21, 22 entrance

23 exit

3 variable converters

31 input

32 output

4 distributors

41 entrance

42, 43 Output a _set delay setpoint at _rain delay _actual value a _out delay manipulated variable

F braking force

Faxie 1 axle braking force

Faxie _n axle braking force

Claims

PATENT CLAIMS

1. Brake control device (2) for a rail vehicle, having an input (21) for a deceleration setpoint (äset), an input (22) for an actual deceleration value (atrain) and an output (23) for a deceleration manipulated variable value (a _ou t) , wherein the delay manipulated variable value (a _ou t) is set by a control unit to avoid a deviation between the actual delay value (atrain) and the

Minimize deceleration setpoint (a _se t), characterized in that a

Limiting device is present that limits the delay manipulated variable value (a _ou t) independently of the control unit in such a way that the delay manipulated variable value (a _ou t) from the delay setpoint value (aset) at most by a maximum negative control stroke (14) to smaller values or deviates from larger values by at most a maximum positive control stroke (15).

2. Brake control device (2) according to claim 1, in which at least one of the two maximum control strokes (14, 15) is not proportional to the deceleration setpoint (a _set ).

3. Brake control device (2) according to claim 1 or 2, in which a sum of the maximum negative control stroke (14) and the maximum positive control stroke (15) is a predetermined fixed value.

4. Brake control device (2) according to one of claims 1 to 3, in which the maximum negative control stroke (14) is not equal to the maximum positive control stroke (15).

5. Brake control device (2) according to one of claims 1 to 4, in which the negative maximum control stroke (14) and / or the positive maximum control stroke (15) are time-dependent.

6. Brake control device (2) according to claim 5, in which the negative maximum control stroke (14) and / or the positive maximum control stroke (15) are reduced after a predetermined braking time.

7. Brake control device (2) according to claim 4 or 5, in which the positive maximum control stroke (15) is only time-dependent when the deceleration setpoint (äset) is below a predetermined limit value.

8. Brake control device (2) according to one of claims 5 to 7, in which the negative minimum control stroke (14) is only time-dependent when the deceleration setpoint (a _set ) is above a further predetermined limit value.

9. Brake control device (2) according to one of claims 1 to 8, wherein at least one of the two maximum control strokes (14, 15) by one of the

Delay setpoint (a _set ) and / or the braking time-dependent characteristic curve or a family of characteristics is specified.

10. Brake control device (2) according to one of claims 1 to 9, in which at least one of the two maximum control strokes (14, 15) is dependent on external influencing variables.

11. Brake control device (2) according to claim 10, in which the external influencing variables are ambient conditions such as temperature or humidity.

12. Brake control device (2) according to claim 10 or 11, wherein the external

Influencing variables are driving conditions of the rail vehicle, in particular a driving speed, a brake pressure, a braking force and / or an activation of an anti-skid system and / or a sand system and / or a

Magnetic rail brake.

13. Brake control device (2) according to one of claims 1 to 12, in which the

Limiting device is coupled to the control unit in order to act on parameters of the control unit depending on a limitation.

14. Operating method for a braking system of a rail vehicle in which a deceleration manipulated variable value (a _ou t) is set by a control unit as a function of a deceleration setpoint (a _se t) and an actual deceleration value (atrain) in order to achieve a To minimize the deviation between the actual delay value (atrain) and the nominal delay value (äset), characterized in that the delay manipulated variable value (a _ou t) is limited independently of the control unit in such a way that the delay manipulated variable value (a _ou t) depends on the delay setpoint (a _se t) can deviate at most by a maximum negative control stroke (14) to smaller values or at most by a maximum positive control stroke (15) to larger values.

15. Operating method according to claim 14, in which at least one of the two maximum control strokes (14, 15) is not proportional to the deceleration setpoint (a _set ).

16. Operating method according to claim 14 or 15, in which at least one of the two maximum control strokes (14, 15) is determined depending on the deceleration setpoint (a _set ) and / or the braking time and / or ambient conditions and / or driving conditions.

17. Brake system for a rail vehicle, comprising a brake control device (2) according to one of claims 1 to 16.